The present invention relates to a device for rolling up sheets, which device is adapted to be coupled to a printing unit for printing sheets, and comprises a first transport path for conveying a printed sheet away from the printing unit, and a roll-forming space adjoining the first transport path for rolling up therein the printed sheet supplied through the first transport path.
A device of this kind is known from Netherlands Patent Application 1005209. When printed sheets are rolled up, the printed side of a turn comes into contact with the surface of the sheet of an adjoining turn. This may result in damage to the image and soiling of the sheet, for example if the image is formed by ink which is not yet dry during the rolling up of the sheet. This undesirable effect can occur particularly in the printing of sheets with ink which does not dry very rapidly, as may be the case in inkjet printing.
From DE-A 40 29 673 it is known to prevent these unwanted effects in the rolling up of a sheet by waiting sufficiently long after printing before rolling up the sheet.
In the ink-printing of sheets which are to be stacked it is also known to heat the sheets prior to stacking, heating being effected by a heating element in order to dry the ink (U.S. Pat. No. 4 774 523), or to keep the sheets in a stack separated by spacers until the ink is dry (U.S. Pat. Nos. 5 429 349 and 5 544 876).